A bicyclist was slammed by an MTA bus on Thursday afternoon — and is clinging to life in the hospital, officials said.

The cyclist was riding on Kissena Boulevard near the intersection of Peck Avenue in Flushing at about 1 pm when the bike crossed over the center line and crashed into a Q17 bus that was headed in the opposite direction.

Emergency services took the cyclist to Booth Memorial Hospital.

No one on the bus was injured, and all passengers were transferred to another vehicle, MTA officials said.